Pre-Clinical Validation of A Novel Continuous Intra-Abdominal Pressure Measurement Equipment (SERENNO)

Introduction: Increased intra-abdominal pressure (IAP) has an important impact on morbidity and mortality in critically ill patients. The SERENNO Sentinel system (Serenno Medical, Yokne’am Illit, Israel) is a novel device that allows automatic and continuous IAP measurements. Aims: Pre-clinical validation in a bench model study comparing the new device with the gold standard method and two other continuous IAP measurement devices. Methods: IAP measurement with the novel SERENNO device (IAP(SER)) was compared with the gold standard IAP(H2O) (water column height) and two other automatic and continuous IAP measurement devices: IAP(CiM) measured via the CiMON device (Pulsion Medical Systems, Munich, Germany) and IAP(SPIE) measured using the Spiegelberg device (Spiegelberg, Hamburg, Germany), which previously received the CE mark for clinical applications. The IAP measurement was performed six times (n = 6) at each pressure value (between 0 and 35 mmHg) with different methods and the height of the water column in a bench-top phantom was used as the reference IAP for further interpretations. In addition to the quadruple comparisons, intra- and inter-observer variability of IAP measurements were also calculated. Correlation studies and Bland and Altman’s analyses were performed in addition to the concordance study. Results: The CiMON and Spiegelberg devices showed a greater dynamic range and standard deviation when recording IAP(CiM) and IAP(SPIE) compared with IAP(SER). In general, the maximum and minimum values of IAP recorded with each device (at each level of IAP(H2O)) were significantly different from each other. However, the average values were in very good agreement. The highest correlation was observed between IAP(SER) and IAP(H2O), and IAP(SER) and IAP(SPIE) (R = 0.99, p = 0.001 for both comparisons and intra- and inter-observer measurements). Although the CiMON and SERENNO systems were in very good agreement with each other, a slightly smaller correlation coefficient was found between them (R = 0.95, p = 0.001, and R = 0.96, p = 0.001 for intra- and inter-observer measurements, respectively). When compared to the gold standard (IAP(H2O)), Bland and Altman’s analysis showed a mean difference of +0.44, −0.25, and −0.04 mmHg for the intra-observer measurements and +0.18, −0.75, and −0.58 mmHg for the inter-observer measurements for IAP(SER), IAP(CiM), and IAP(SPIE), respectively. IAP(SER) showed a small positive bias (overestimation), while IAP(CiM) and IAP(SPIE) showed a negative bias (underestimation) when compared to IAP(H2O). Further statistical analysis showed a concordance coefficient of 100% with an excellent ability of the SERENNO system in tracking IAP(H2O) changes. Conclusions: Pre-clinical validation of a new IAP monitoring device (SERENNO) showed very promising results when compared with the gold standard and other continuous techniques; however, clinical trials should be followed as the next stage of the validation process. Based on the actual research guidelines, the SERENNO system can be used interchangeably with the gold standard.